Electric rotating machine for vehicle

ABSTRACT

Reductions in cost and manufacturing processes are achieved by interposing a single metallic terminal between a lead wire of a stator and a three-phase output terminal. A rotor  3  is fixed onto a rotating shaft  2  disposed rotatably in a housing  1,  and a stator core  5  is disposed opposite to the rotor  3.  A stator winding  6  is wound around the stator core  5  and a lead wire  10  of the stator winding  6  is connected to a head portion  8   a  of a three-phase output terminal  8  through a single metallic terminal by a screw  12.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an electric rotating machine forvehicle and, more particularly, to improvement in connection of a statorwinding thereof.

2. Description of the Related Art

FIG. 8 is a sectional view showing a conventional electric rotatingmachine for vehicle. In the drawing, numeral 21 designates a frontbracket, numeral 22 designates a rear bracket and numeral 23 designatesa rotor. The rotor 23 includes a rotating shaft 24, field cores 25 a and25 b, a field winding 26, and cooling fans 27 a and 27 b. Both frontbracket 21 and rear bracket 22 support the rotating shaft 24 throughbearings 28 a and 28 b. The field cores 25 a and 25 b are of Randel-typeand the field winding 26 is internally wound thereon.

The field cores 25 a and 25 b are fitted into the rotating shaft 24 androtate integrally with the rotating shaft 24. The cooling fans 27 a and27 b are fixed onto sides of the field cores 25 a and 25 b respectively.Numeral 29 designates an armature acting as a stator, which includes anarmature core 30 acting as a stator core and an armature winding 31acting as a stator winding. The armature winding 31 is inserted into aslot of the armature core 30, and a coil end of the armature winding 31protrudes from the armature core 30 in the axial direction. The armaturecore 30 has an internal peripheral wall forming a cylindrical hollowportion, and the rotor 23 is inserted in this hollow portion.

In the conventional electric rotating machine for vehicle of aboveconstruction, a three-phase output terminal 32 and a lead wire 33 of thestator are connected through a metallic terminal 34, which is connectedto the lead wire 33 of a winding wound around the stator core 30, andthrough a metallic terminal 36, which is embedded in an insulator 35made of resin.

Since the conventional electric rotating machine for vehicle has beenconstructed as described above, plural metallic terminals areessentially required between the three-phase output terminal and thelead wire of the winding wound around the stator core. Accordingly, aproblem exists in that excessive cost and complicated manufacturingprocesses have been required.

Moreover, since there are metallic terminals formed by resin molding, afurther problem exists in that combustion loss may occur if a largecurrent passes through, and that resistance of the metallic terminalbrings about reduction in both output and efficiency.

SUMMARY OF THE INVENTION

The present invention has been made to solve the above-discussedproblems and has an object of reducing not only cost and manufacturingprocesses but also resistance of the metallic terminal in order toimprove output and efficiency by interposing just a single metallicterminal between a lead wire of a stator and a three-phase outputterminal.

An electric rotating machine for vehicle of the invention includes arotor fixed onto a rotating shaft disposed in a housing, a stator coredisposed opposite to the rotor, a stator winding wound around the statorcore, and a three-phase output terminal to which a lead wire of thestator winding is connected. And the lead wire is connected to thethree-phase output terminal through a single metallic terminal. As aresult, not only cost and manufacturing processes but also resistance isreduced, and therefore output and efficiency are improved.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partially sectional view showing an electric rotatingmachine for vehicle according to Embodiment 1 of the present invention;

FIG. 2 is a partially sectional view showing an electric rotatingmachine for vehicle according to Embodiment 2 of the invention;

FIG. 3 is a front view showing a connection part between a lead wire anda three-phase output terminal;

FIG. 4 is a front view showing a lead wire according to Embodiment 3 ofthe invention;

FIG. 5 is a sectional view showing a three-phase output terminal partaccording to Embodiment 4 of the invention;

FIG. 6 is a front view taken in the direction A of FIG. 5;

FIG. 7 is a front view showing a connection part between a lead wire anda three-phase output terminal; and

FIG. 8 is a sectional view showing a conventional electric rotatingmachine for vehicle;

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1

An embodiment of the present invention is hereinafter described withreference to the accompanying drawings.

FIG. 1 is a partially sectional view showing an electric rotatingmachine for vehicle according to Embodiment 1 of the invention, and inwhich the electric rotating machine for vehicle starts an engine byacting as a motor and supplies power to the vehicle by acting as agenerator.

In the drawing, numeral 1 designates a housing, numeral 2 designates arotating shaft disposed in the housing 1 and numeral 3 designates arotor fixed onto the rotating shaft 2. Numeral 4 designates a fieldwinding wound around the rotor 3, numeral 5 designates a stator coredisposed opposite to the rotor 3 and numeral 6 designates a statorwinding wound around the stator core 5. Numeral 7 designates a coolingfan and numeral 8 designates a three-phase output terminal for takingout output from the stator.

Further, the three-phase output terminal 8 is provided with a threadedhole 9. At least one of lead wires 10 of the stator winding 6 woundaround the stator core 5 is connected to the three-phase output terminal8 through a single metallic terminal 11 by screwing with a screw 12.

The three-phase output terminal 8 is fixed at an external part of thehousing 1 with an insulator 13 such as resin, and the insulator 13 isfixed to the housing 1. It is also preferable that the output terminal 8is fixed at an internal part of the housing 1.

In this manner, since the single metallic terminal 11 interposes betweenthe lead wire 10 and the three-phase output terminal 8, not only costand manufacturing steps but also resistance is reduced, and as a resultoutput and efficiency are improved.

Further, since any metallic terminal embedded in an insulator made ofresin or the like is not required unlike the conventional technique, anycombustion loss does not occur. Since the metallic terminal 11 isexposed, cooling efficiency is improved.

Furthermore, since a screw 12 connects the three-phase output terminal 8and the lead wire 10 through the metallic terminal 11 by screwing,assembling becomes easier and manufacturing cost is reduced.

Additionally, an air-cooling system provided with the cooling fan 7 isadopted and cools around the lead wire 10 by cooling wind, theconstruction becomes simpler than that of water-cooling system.

Embodiment 2

FIG. 2 is a partially sectional view showing an electric rotatingmachine according to Embodiment 2 of the invention. In this embodiment,a head portion 8 a of a three-phase output terminal 8 is provided with amale screw 8 b. A nut 15 connects at least one of the lead wires 10 ofthe stator winding 6 wound around the stator core 5 to the three-phaseoutput terminal 8 through just a single metallic terminal 14.

In this manner, since a connection part between the lead wire 10 and thethree-phase output terminal 8 is formed at the head portion 8 a of thethree-phase output terminal 8, the connection becomes easier.

Further, since the three-phase output terminal 8 and the metallicterminal 14 as well as the lead wire 10 of the stator winding 6 woundaround the stator core 5 are fixed with the nut 15, strength of thethree-phase output terminal 8 is sufficiently secured.

Furthermore, since the connection part between the lead wire 10 and thethree-phase output terminal 8 is disposed at internal part of thehousing 1, it becomes scarcely exposed to water, and therefore thecorrosion-resistance is improved.

In case that Y-connection is adopted on the stator side and the statorwindings are not connected in parallel, one single lead wire 10 issufficient. However, in case that Y-connection is adopted on the statorside and the stator windings are connected in parallel, or in case thatdelta-connection is adopted on the stator side, plural than lead wires10 are required. To cope with this, it is also preferable that the nut15 connects the plural metallic terminals 14 with the three-phase outputterminal 8, as shown in FIG. 3.

Embodiment 3

This embodiment is the same as the foregoing Embodiment 2 in the aspectthat the head portion 8 a of the three-phase output terminal 8 isprovided with the male screw 8 b. In this embodiment, however, at leastone lead wire 10 of the stator winding 6 wound around the stator core 5is directly connected with the three-phase output terminal 8 with a nut15, thus the metallic terminal 14 being omitted.

FIG. 4 is a front view showing the lead wire 10. Top end portion of thelead wire 10 is crushed so as to be provided with a hole 10 a, throughwhich the male screw 8 b on the head portion 8 a side of the three-phaseoutput terminal 8 is inserted.

Although a nut is employed for fixation in the above description, it isalso preferable that a screw is employed for fixation.

As described above, since no metallic terminal is interposed between thelead wire 10 and the three-phase output terminal 8, not only cost andmanufacturing processes but also resistance are reduced, eventuallyresulting in improvement of output and efficiency.

Embodiment 4

In this embodiment, at least one of lead wires 10 of the stator winding6 wound around the stator core 5 is connected by TIG welding directly tothe three-phase output terminal 8 on the head portion 8 a side.

FIG. 5 is a sectional view showing the three-phase output terminal 8portion and FIG. 6 is a front view taken in A direction of FIG. 5.

In the drawings, the lead wire 10 is put on a groove 16 provided on thehead portion 8 a of the three-phase output terminal 8, and the lead wire10 and the three-phase output terminal 8 are directly connected by TIGwelding B.

Instead of welding, the lead wire 10 maybe connected by brazing.

Furthermore, as shown in FIG. 7, the lead wire 10 maybe connected to thehead portion 8 a of the three-phase output terminal 8 by caulking, inwhich caulking punch is applied to C portions.

As described above, the three-phase output terminal 8 and the lead wire10 of the stator winding 6 wound around the stator core 5 are connectedby welding, caulking at the three-phase output terminal head portion 8 aor brazing without any connection member. As a result, no part such asscrew or nut is required, eventually resulting in further costreduction.

While the presently preferred embodiments of the present invention havebeen shown and described.

It is to be understood that these disclosures are for the purpose ofillustration and that various changes and modifications may be madewithout departing from the scope of the invention as set forth in theappended claims.

1. (canceled)
 2. An electric rotating machine for vehicle comprising: arotor fixed onto a rotating shaft disposed in a housing, a stator coredisposed opposite to said rotor, a stator winding wound around saidstator core, and a three-phase output terminal to which a lead wire ofsaid stator winding is connected; wherein said lead wire is directlyconnected to said three-phase output terminal.
 3. (canceled)
 4. Anelectric rotating machine for vehicle according to claim 2, wherein ascrew connects said lead wire to said three-phase output terminal. 5.(canceled)
 6. An electric rotating machine for vehicle according toclaim 2, wherein a nut connects said lead wire to said three-phaseoutput terminal.
 7. An electric rotating machine for vehicle accordingto claim 2, wherein said lead wire and said three-phase output terminalare connected by welding.
 8. An electric rotating machine for vehicleaccording to claim 2, wherein said lead wire and said three-phase outputterminal are connected by caulking.
 9. An electric rotating machine forvehicle according to claim 2, wherein said lead wire and saidthree-phase output terminal are connected by brazing.
 10. (canceled) 11.An electric rotating machine for vehicle according to claim 2, whereinthe connection part between said lead wire and said three-phase outputterminal is disposed at a head portion of said three-phase outputterminal.
 12. (canceled)
 13. An electric rotating machine for vehicleaccording to claim 2, wherein the connection part between said lead wireand said three-phase output terminal is disposed at an internal part ofsaid housing.
 14. (canceled)
 15. An electric rotating machine forvehicle according to claim 2, wherein a cooling system for coolingaround said lead wire is of air-cooling type.